I just installed my JB4 today. I had a JB+ all this while and I was satisfied with it. But the itch for a faster car, or something comparable to my B9 A4, kept nagging me. I scoured various forums for used units since a new one ends up being a wee bit expensive for me. Another thing that held me back was the complicated (to me) install (the complicated part being the routing of the OBD2 cable for the CANbus operation).
I struck gold a few days ago and managed to snag a slightly used unit for a good deal. The seller
ovox0 turned out to be a nice guy who answered all my questions. I didn’t even have to open it up to install the JB connect kit since he had already done it. And most importantly, he shipped it out real fast and it reached me in 2 days flat.
Uninstalling the JB+ took all of 10 seconds. Literally. I was worried about breaking the TMAP sensor clip since I already broke the MAP sensor clip when I first tried to install the JB+. Luckily, the second I removed the lock, the clip popped right off without me even having to apply any force. I was surprised at how easy it was. Installing the two wires from the piggy back as another ten second affair (Just make sure to clip the TMAP sensor wire in properly since I hadn’t and even drove around with it unplugged. The car kept throwing a CEL (absolute manifold pressure low) and I thought it was probably a faulty unit or something until I rechecked the connections and found out that the TMAP clip had become completely undone. The location of the sensor made it difficult for me to properly clip it in but once that was done, all was well again and no CELs).
For the OBD2 cable, I went the easy route and installed it through the door jamb and into the hood instead of poking through the firewall. The upside is it takes less than a minute to do it. Downside is that the wire is visible when the door is open but I don’t care. It works. It’s easy to install and uninstall the entire unit in a minute or less. That’s all that matters to me.
I used the JB4 mobile app to go to map 2 directly since I had read that map 1 was only slightly better than a JB+ and it was also for 91 octane fuel. I made sure there were no errors and stuff and backed out of the garage gingerly. Drove out of the community and floored it on an empty stretch of road. The only thing that came out of my mouth was wow! My wife was with me and I had warned her. She also let out a gasp as the car accelerated. We both looked at each other and she said “Well yes. That thing definitely works”.
I did not expect to find a noticeable difference between the JB+ and JB4 and boy, was I wrong. The car pulls much harder now. And this is without even driving much except for the engine to warm up. I couldn’t drive much but whatever little I drove, I loved. It was like driving a whole new car again. And she feels as fast as my B9 A4 was! Maybe even a wee bit more
The JB+ had a noticeable boost once the turbo spooled up. The lag felt exaggerated. With the JB4, the turbo spooling up feels even better. The lag before the turbo spools up doesn’t feel bad at all. It is definitely smoother than the JB+.
The car also doesn’t feel like it runs out of steam at higher rpms.
So was it worth it? Absolutely. It’s worth every penny (or cent) I paid for it. I’m so glad I decided to get the JB4.
I’ll post more once I get some more seat time in the car. Alone.